mod_auth_dovecot: Only check Dovecot major version. Bump log level from 'warn' to 'error'. (thanks Adrien Clerc)
-- Dovecot authentication backend for Prosody
--
-- Copyright (C) 2010 Javier Torres
-- Copyright (C) 2008-2010 Matthew Wild
-- Copyright (C) 2008-2010 Waqas Hussain
--
local socket_unix = require "socket.unix";
local datamanager = require "util.datamanager";
local log = require "util.logger".init("auth_dovecot");
local new_sasl = require "util.sasl".new;
local nodeprep = require "util.encodings".stringprep.nodeprep;
local base64 = require "util.encodings".base64;
local pposix = require "util.pposix";
local prosody = _G.prosody;
local socket_path = module:get_option_string("dovecot_auth_socket", "/var/run/dovecot/auth-login");
function new_default_provider(host)
local provider = { name = "dovecot", request_id = 0 };
log("debug", "initializing dovecot authentication provider for host '%s'", host);
local conn;
-- Closes the socket
function provider.close(self)
if conn then
conn:close();
conn = nil;
end
end
-- The following connects to a new socket and send the handshake
function provider.connect(self)
-- Destroy old socket
provider:close();
conn = socket.unix();
-- Create a connection to dovecot socket
log("debug", "connecting to dovecot socket at '%s'", socket_path);
local r, e = conn:connect(socket_path);
if (not r) then
log("warn", "error connecting to dovecot socket at '%s'. error was '%s'. check permissions", socket_path, e);
provider:close();
return false;
end
-- Send our handshake
local pid = pposix.getpid();
log("debug", "sending handshake to dovecot. version 1.1, cpid '%d'", pid);
if not provider:send("VERSION\t1\t1\n") then
return false
end
if (not provider:send("CPID\t" .. pid .. "\n")) then
return false
end
-- Parse Dovecot's handshake
local done = false;
while (not done) do
local l = provider:receive();
if (not l) then
return false;
end
log("debug", "dovecot handshake: '%s'", l);
parts = string.gmatch(l, "[^\t]+");
first = parts();
if (first == "VERSION") then
-- Version should be 1.1
local major_version = parts();
if major_version ~= "1" then
log("error", "dovecot server version is not 1.x. it is %s.x", major_version);
provider:close();
return false;
end
elseif (first == "MECH") then
-- Mechanisms should include PLAIN
local ok = false;
for p in parts do
if p == "PLAIN" then
ok = true;
end
end
if (not ok) then
log("warn", "server doesn't support PLAIN mechanism. It supports '%s'", l);
provider:close();
return false;
end
elseif (first == "DONE") then
done = true;
end
end
return true;
end
-- Wrapper for send(). Handles errors
function provider.send(self, data)
local r, e = conn:send(data);
if (not r) then
log("warn", "error sending '%s' to dovecot. error was '%s'", data, e);
provider:close();
return false;
end
return true;
end
-- Wrapper for receive(). Handles errors
function provider.receive(self)
local r, e = conn:receive();
if (not r) then
log("warn", "error receiving data from dovecot. error was '%s'", socket, e);
provider:close();
return false;
end
return r;
end
function provider.send_auth_request(self, username, password)
if not conn then
if not provider:connect() then
return nil, "Auth failed. Dovecot communications error";
end
end
-- Send auth data
username = username .. "@" .. module.host; -- FIXME: this is actually a hack for my server
local b64 = base64.encode(username .. "\0" .. username .. "\0" .. password);
provider.request_id = provider.request_id + 1 % 4294967296
local msg = "AUTH\t" .. provider.request_id .. "\tPLAIN\tservice=XMPP\tresp=" .. b64;
log("debug", "sending auth request for '%s' with password '%s': '%s'", username, password, msg);
if (not provider:send(msg .. "\n")) then
return nil, "Auth failed. Dovecot communications error";
end
-- Get response
local l = provider:receive();
log("debug", "got auth response: '%s'", l);
if (not l) then
return nil, "Auth failed. Dovecot communications error";
end
local parts = string.gmatch(l, "[^\t]+");
-- Check response
local status = parts();
local resp_id = tonumber(parts());
if (resp_id ~= provider.request_id) then
log("warn", "dovecot response_id(%s) doesn't match request_id(%s)", resp_id, provider.request_id);
provider:close();
return nil, "Auth failed. Dovecot communications error";
end
return status, parts;
end
function provider.test_password(username, password)
log("debug", "test password '%s' for user %s at host %s", password, username, module.host);
local status, extra = provider:send_auth_request(username, password);
if (status == "OK") then
log("info", "login ok for '%s'", username);
return true;
else
log("info", "login failed for '%s'", username);
return nil, "Auth failed. Invalid username or password.";
end
end
function provider.get_password(username)
return nil, "Cannot get_password in dovecot backend.";
end
function provider.set_password(username, password)
return nil, "Cannot set_password in dovecot backend.";
end
function provider.user_exists(username)
log("debug", "user_exists for user %s at host %s", username, module.host);
-- Send a request. If the response (FAIL) contains an extra
-- parameter like user=<username> then it exists.
local status, extra = provider:send_auth_request(username, "");
local param = extra();
while (param) do
parts = string.gmatch(param, "[^=]+");
name = parts();
value = parts();
if (name == "user") then
log("info", "user '%s' exists", username);
return true;
end
param = extra();
end
log("info", "user '%s' does not exists (or dovecot didn't send user=<username> parameter)", username);
return false;
end
function provider.create_user(username, password)
return nil, "Cannot create_user in dovecot backend.";
end
function provider.get_sasl_handler()
local realm = module:get_option("sasl_realm") or module.host;
local getpass_authentication_profile = {
plain_test = function(sasl, username, password, realm)
local prepped_username = nodeprep(username);
if not prepped_username then
log("debug", "NODEprep failed on username: %s", username);
return "", nil;
end
return usermanager.test_password(prepped_username, realm, password), true;
end
};
return new_sasl(realm, getpass_authentication_profile);
end
return provider;
end
module:add_item("auth-provider", new_default_provider(module.host));